The 2011 GM Volt is generating
unprecedented hype as the highest profile upcoming mass-market
electric vehicle. With the U.S. government and automakers
worldwide all betting big on electric vehicles, General Motors has
done perhaps the best job at promoting its upcoming vehicle.

The
vehicle is currently in the pre-production
testing phase, in which the final bugs in the prototypes are
ironed out via minor changes, largely to the vehicle's software and
mechanical settings. A fleet of prototype Volts completed a
long
test-drive journey and engineers are now using the data collected
to tweak the Volt. They hope to minimize
its problems in the process.

James Riswick, an editor with
Edmunds.com, recently took one of the mules out
for a test drive to measure their progress on this front.
He reports, "[The Volt] is sort of on the more fun to drive
hybrid. The suspension is a little firmer, than say, in the
Prius, which is on the floaty, comfortable side. This is not a
sports car by any means, but actually the electric power steering is
reasonably direct and well weighted."

In his opinion, the
noise when driving under gasoline generator is minimal and seems like
"white noise". However, when stopping, a more "rough"
unpleasant sound was heard – GM says they're working on this
issue. Overall, Riswick says the car is "pretty darn
normal" and that "It drives like a pretty nice
car"

However, as many have noted a couple of pivotal
unknowns remain -- the Volt's finalized real world gas mileage and
cost. The Volt will be available in all 50 states when it
debuts, according to GM. It will be available for around
$40,000, plus a $7,500 federal tax credit, which brings it to
approximately $32,500 (excluding additional hybrid tax breaks in
certain states). However, this price could be bumped
significantly higher or lower still.

The vehicles will
currently recharge in about 8 hours household 120-volt current, while
special 240-volt charging stations can charge it in only 3 hours.
GM estimates the car's fuel economy to
be 230 mpg, but this value has yet to be confirmed in real world
independent testing. One of GM's top priorities has been trying
to tweak the gas mileage upwards during the testing cycle.

One
detail that has not been widely publicized is the new vehicle's
"sports mode". Activated by a Sport button on the
center stack, the feature makes the throttle more receptive and
increases its ultimate limit, bumping 0 to 60 mph acceleration down
to 9 seconds. The Volt's urge to scoot increases in the mode,
though. Like most cars, the Volt also provides an electronic
version of a "Low" gear similar to that found in normal
cars, which allows faster deceleration. GM recommends the Low
mode for driving on slopes or in stop and go.

One
disappointment is that the Volt and other Lithium-ion battery-powered
electric vehicles may not be viable in hotter climates, such as some
states in the American Southwest. Despite the fact that Volts
will be sold in these states, performance may be significantly
undermined due to the heat. Volt Chief Engineer Andrew Farah
describes, "The Volt may not be right for everyone. If you live
in the Southwest, depending on how you use your car, the Volt might
not be right for you."

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Volt has an electric drive train. The electric drive train will have a maximum of 110 kW availble at all times (roughly ~150 hp) with an impressive amount of twist.

The Volt has an automatic electric fueling system in an range extender. This range extender is powered by gasoline. Its true that the range extender can only provide around 53 kW of power (enough to travel 100 mph on a flat road) which might limit performance if not for the large battery that acts as a buffer. The Prius uses approx .5 kWh of its battery as a buffer. The Volt's 30% SOC should be 4.8 kWh! large. Enough to provide a similar buffer to the Prius or even larger for years to come.

Similar to the Prius, the Volt will have reduced performance when it runs out of its buffer. But similar to a Prius this will be relatively hard to accomplish

53 kW if the engine is running at full power, which would be pretty loud, and then you have to take into account the efficiency of electricity generation and battery charging and then the efficiency of battery discharging, and the efficiency of the electric motor (Tesla hand-wound motor is claimed to be 92.5% efficient), so starting with the gasoline in the tank, you lose a lot of energy as heat by the time the power gets to the wheels, because of your "buffer".

Prius does this in a much smarter way with its revolutionary transmission that can efficiently connect two motive sources to the same set of wheels. Its always more efficient to convert mechanical energy to mechanical energy via gears then to first convert it to electricity via a generator, then back into mechanical energy via a motor.

And this is why I don't think the volt will stand up to the Prius, especially when it gets a larger battery+plug in option from the factory.

Nope. Maximum right now is 4,000 rpm on a NA 4 cylinder? = Not audible over most HWY road noises. Heck, most cars with 4 cylinders at 1.4L require over 3,000 RPM for HWY speeds (Like the Civic). Is that engine really noisy on the HWY?

Nope. Electricity from the Generator goes right to the Wheels. No stop over in the Battery. GM has stated that the Generator alone is capable upto nearly 100 mph in testing.

quote: Prius does this in a much smarter way with its revolutionary transmission that can efficiently connect two motive sources to the same set of wheels. Its always more efficient to convert mechanical energy to mechanical energy via gears then to first convert it to electricity via a generator, then back into mechanical energy via a motor.

Why bother commenting at all if you have a fundamental belief that doesn't accept argument? I'd be careful. Gears are not all that great you know? Ever do gear design? Even the finest machined gears lose power/efficiency. A planetary set of gears will especially lose something.

The Volt does the same thing as a Prius, but takes it a step further. The Prius also takes ICE engery --> Battery (buffer) ---> Motor ---> Mechanical Boost.

The Prius gasoline engine is still directly responsive to input loads as the Mechanical Boost provided by the Prius engine is a measily 27 kW (from the Battery). This is insufficient at higher speeds and more than .... turtle like acceleration. The Volt's generator is free to run closer to maximum efficieny all the time.

The Volt's ICE generator will have the potential to be more efficient than the Pruis engine. Its true in ER mode, the Volt may get less MPG than a Prius by a small smidge (after all the 1.8L Atkinson has a higher maximum efficieny point than a 1.4L NA Otto engine!) but guess whats the best part? For a normal driver, the ICE generator will run less than 25% of the time! (Where-as for the Prius driver, the ICE is always running)

Even with no stopover at battery, generator+motor, assuming 10% efficiency loss at each step, gives you 19% loss. A 90% electric motor is considered very good, and the generator is assumed to be as efficient as the motor.(100*0.10)+(90*0.10)=19%FWD drivetrain (the inefficient gears that you mention) losses are about 10-12% with small cars that don't make a lot of power.

Furthermore, you are misinformed about the Prius, it can run in EV mode as well. All they need to do is enlarge the motor and the battery pack, connect it to the same wonder transmission, and all advantages of Volt are negated, whereas the drivetrain efficiency and the atkinson cycle engine efficiency advantages remain over the Volt.

As long as more than 27 kW are not required. (More like 22 kW, because of the "magical" tranmission system. The Volt's 110kW goes through a fixed one gear with high high efficieny of transmission of power)

As noted earlier, the Prius entire battery is 0.5 kWh, so thats what? 1.2 minutes of full EV mode! or around 3 minutes at 40 mph. Oh yes, a wonderful EV mode.

"Furthermore, you are misinformed about the Prius, it can run in EV mode as well. All they need to do is enlarge the motor and the battery pack, connect it to the same wonder transmission, and all advantages of Volt are negated, whereas the drivetrain efficiency and the atkinson cycle engine efficiency advantages remain over the Volt. "

You mean. All they have to do is turn it into a Volt and the Prius is better than a Volt? A -fourth- generation product developed drastically into what would be its -fifth- or -sixth- product cycle is more efficient than a -first-?Go back and look at the JDM Prius or even the first one that came to the US. Compare the Volt to that thing... The Volt has the potential in the 3rd or 4th generation that is something truely special. 60 mpg+ CS modes. 50 miles AER. 200 hp+ AWD. Prius? Not so much so, at least not without -becoming- a Volt.

It's not that hard to build a bigger electric motor, or a battery pack, only reason Prius doesn't have it is because it's designed to be sold in the 20k+ range unlike the Volt which is in the 40k range.

Generators, motors, and batteries have been around for years. Diesel electric locomotives use it due to the complexity/cost of designing a mechanical transmission that can withstand so much torque and the load of 100+ fully loaded cars. There's a reason why cars don't use the same propulsion system, and it's called efficiency.

Coming up with a transmission and hybrid system like in the Prius shows real ingenuity and impresses me much more. And mark my words, it will show its results in the real world fuel mpg when both don't have access to a plug.

Also, the "weak" Prius gets 0-60 around 9 seconds, same as the Volt, which is enough for a family car.

The reason why cars haven't used the system is due to wieght and rolling resistence and space.

A train on proper tracks has incredibly small rolling resistence combined with relatively high volume.

Until Lithium Ion, Batteries have not provided the required Power, Capacity, and Density to be used in the Volt fashion.

Now that Lithium Ion is approaching a reasonable cost, every automaker is suddenly throwing together electric cars or plug-ins. Including Prius Plug-ins.

"Coming up with a transmission and hybrid system like in the Prius shows real ingenuity and impresses me much more. And mark my words, it will show its results in the real world fuel mpg when both don't have access to a plug."

Why in the world would you buy a Volt and not plug it in??????????? Maybe we should buy a Prius and use it as farm equipment?!? or a drag racer?!?

When used as intented, the Volt is much more energy efficient, operating cost efficient, and uses much much less critical resource (Oil more critical than Coal, NG, Nuclear, Wind, Solar, etc) than a Prius.

The main energy saving effect of diesel-mechanic compared to diesel-hydromechanic and diesel-electric propulsion comes from better efficiency of transmission. According to DSB, mechanic transmission has an efficiency of ~ 95 % compared to ~85 % for the other two systems. This alone yields energy savings of about 10 %.

For less heavy commuter trains, the interest is actually returning to diesel-mechanical transmissions due to higher efficiency.

Prius is the best of both worlds right now, and can be easily modified to fend off the volt by adding a more powerful electric motor and a bigger battery pack. This will of course increase its cost.

"Its always more efficient to convert mechanical energy to mechanical energy via gears then to first convert it to electricity via a generator, then back into mechanical energy via a motor."

Yeah, that's why diesel-electric locomotives use direct drive from the diesel engine to the wheels on the rail, right? Oops. They don't do that. They run a generator and use electricity to drive the wheels.

Gears are inherently inefficient due to friction and gear slip. A train of 2 gear sets with 90% efficiency each result in only 81% efficiency at the output shaft, and that's ignoring everything *except* tooth friction losses.

As I said above, a transmission that's robust enough to move a train is hard to actually fit into a train. If diesel electric was that efficient, you'd also see it used in trucks, instead of 18-speed transmissions.